Method and apparatus for an integrated GPS receiver and electronic compassing sensor device

ABSTRACT

At least one magnetic field sensing device and GPS receiver integrated in a discrete, single-chip package, and a method of manufacture for the same. Rather than requiring at least two separate chips to be used to realize GPS positioning and compassing capabilities in a single device, an integrated, single chip solution can be used. A single chip integration of a GPS receiver and at least one magnetic field sensing device can reduce the physical space required to provide positioning and electronic compassing capabilities in a single device, and therefore allow such devices to be smaller, lighter, and possibly more portable.

RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application Nos.(1) 60/475,191, filed Jun. 2, 2003, entitled “Semiconductor DeviceIntegration with a Magneto-Resistive Sensor,” naming as inventors LonnyL. Berg and William F. Witcraft; (2) 60/475,175, filed Jun. 2, 2003,entitled “On-Die Set/Reset Driver for a Magneto-Resistive Sensor,”naming as inventors Mark D. Amundson and William F. Witcraft; and (3)60/462,872, filed Apr. 15, 2003, entitled “Integrated GPS Receiver andMagneto-Resistive Sensor Device,” naming as inventors William F.Witcraft, Hong Wan, Cheisan J. Yue, and Tamara K. Bratland. The presentapplication also incorporates each of these Provisional Applications intheir entirety by reference herein.

This application is also related to and incorporates by reference U.S.Nonprovisional Application Ser. Nos. (1) 10/754,946, filed concurrently,entitled “Semiconductor Device and Magneto-Resistive SensorIntegration,” naming as inventors Lonny L. Berg, William F. Witcraft,and Mark D. Amundson; and (2) Ser. No 10/754,945, filed concurrently,entitled “Integrated Set/Reset Driver and Magneto-Resistive Sensor,”naming as inventors Lonny L. Berg and William F. Witcraft.

BACKGROUND

1. Field of the Invention

The present invention relates in general to magnetic field and currentsensing, and more particularly to integrating a GPS receiver with acompassing sensor.

2. Description of Related Art

Magnetic field sensors have applications in magnetic compassing, ferrousmetal detection, and current sensing. They may be used to detectvariations in the magnetic field of machine components and in theearth's magnetic field, as well as to detect underground minerals,electrical devices, and power lines. For such applications, ananisotropic magneto-resistive (AMR) sensor, a giant magneto-resistive(GMR) sensor, a colossal magneto-resistive (CMR) sensor, a hall effectsensor, a fluxgate sensor, or a coil sensor that is able to detect smallshifts in magnetic fields may be used.

Magneto-resistive sensors, for example, may be formed using typicalintegrated circuit fabrication techniques. Permalloy, a ferromagneticalloy containing nickel and iron, is typically used as themagneto-resistive material. Often, the permalloy is arranged in thinstrips of permalloy film. When a current is run through an individualstrip, the magnetization direction of the strip may form an angle withthe direction of current flow. As the magnetization direction of thestrip changes relative to the current flow, its effective resistancealso changes. Strip resistance reaches a maximum when the magnetizationdirection is parallel to the current flow, and reaches minimum when themagnetization direction is perpendicular to the current flow. Suchchanges in strip resistance result in a change in voltage drop acrossthe strip when an electric current is run through it. This change involtage drop can be measured and used as an indication of change in themagnetization direction of external magnetic fields acting on the strip.

To form the magnetic field sensing structure of a magneto-resistivesensor, several permalloy strips may be electrically connected together.The permalloy strips may be placed on the substrate of themagneto-resistive sensor as a continuous resistor in a “herringbone”pattern or as a linear strip of magneto-resistive material, withconductors across the strip at an angle of 45 degrees to the long axisof the strip. This latter configuration is known as “barber-polebiasing.” The positioning of conductors in a “barber-pole biasing”configuration may force the current in a strip to flow at a 45-degreeangle to the long axis of the strip. These magneto-resistive sensingstructure designs are discussed in U.S. Pat. No. 4,847,584, Jul. 11,1989, to Bharat B. Pant, and assigned to the same assignee as thecurrent application. U.S. Pat. No. 4,847,584 is hereby fullyincorporated by reference. Additional patents and patent applicationsdescribing magnetic sensor technologies are set forth below, inconjunction with the discussion of FIG. 4.

Magnetic sensors often include a number of straps through which currentmay be run for controlling and adjusting sensing characteristics. Forexample, magnetic sensor designs often include set, reset, and offsetstraps. These straps can improve the performance and accuracy ofmagnetic sensors, but require driver circuitry for proper operation.Such circuitry has typically been located off-chip from the magneticsensor, resulting in space inefficiencies. Similarly, other components,such as operational amplifiers, transistors, capacitors, etc., havetypically been implemented on a separate chip from the magnetic sensor.Both signal conditioning and electrostatic discharge circuitry, forexample, are typically located off-chip. Although such off-chipcircuitry is adequate for many applications, for those where physicalspace is at a premium it would be desirable to have necessary circuitryintegrated into a single-chip magnetic sensor, thereby conserving space.

One consequence of the space inefficiencies of multiple-chip magneticsensors is the stunting of technological advances in the integration ofcompassing and positioning technologies. To take advantage of thefunctionality of both magnetic sensors and positioning technologies, atleast one additional positioning chip is required. The GlobalPositioning System (GPS), the leading positioning technology, enables aGPS receiver to determine its position on the earth from a set ofconcurrently received signals transmitted by at least three of aconstellation of GPS satellites. GPS receivers can also determineheading using the same signals used to determine position. However, inorder to obtain an accurate heading, the GPS receiver must be moving ata speed of at least 10 mph. As a result, GPS has been successfully usedfor positioning in both handheld and vehicle-mounted systems, as well asfor navigation in vehicle mounted systems (when traveling at a speed ofat least 10 mph).

By combining the functionality of a magnetic field sensing device withthat of a GPS receiver, a user can determine both direction (from themagnetic field sensing device) and position (from the GPS receiver),both when stationary and when moving. However, for handheldapplications, such a combination may be unwieldy and inefficient due tothe physical space requirements of a GPS receiver chip, a magnetic fieldsensing device chip, and a potential for additional chips required formagnetic field sensing device circuitry. Thus, a single-chip design thatwould minimize the physical space required to integrate a GPS receiverwith a magnetic field sensing device would be desirable.

SUMMARY

One exemplary embodiment provides a single package sensor device. Thesingle package sensor device is comprised of GPS receiver circuitry anda magnetic field sensing device adjacent to the GPS receiver circuitry.The single-package integration of the GPS receiver circuitry and themagnetic field sensing device can be accomplished in the following twoways: (1) a single-die, single package solution and (2) a multiple-die,single-package solution. Because such an integrated device may bemanufactured as a single package, the user may realize advantages thatinclude possible cost reduction, reduced size, and increasedfunctionality, among others.

These as well as other aspects and advantages of the present inventionwill become apparent to those of ordinary skill in the art by readingthe following detailed description, with appropriate reference to theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the present invention are described withreference to the following drawings, wherein:

FIGS. 1A–1C are simplified block diagrams illustrating embodiments ofthe present invention;

FIGS. 2A–2C are simplified block diagrams illustrating embodiments ofthe present invention with included shielding features;

FIG. 3 is a simplified block diagram illustrating a GPS receiver and amagneto-resistive sensor integrated on a single die in accordance withan embodiment of the present invention;

FIG. 4 is a simplified block diagram illustrating a device-architecturefor a GPS receiver and a magneto-resistive sensor integrated in a singledie in accordance with an embodiment of the present invention;

FIG. 5 is a simplified block diagram illustrating a magneto-resistivesensor with GPS receiver components in accordance with an exemplaryembodiment of the present invention;

FIG. 6 is a simplified block diagram illustrating a typical GPSreceiver;

FIG. 7 is a simplified block diagram illustrating an exemplary use foran integrated GPS receiver and magneto-resistive sensor in accordancewith an embodiment of the present invention; and

FIG. 8 is a simplified block diagram illustrating an exemplary use foran integrated GPS receiver and magneto-resistive sensor in accordancewith an embodiment of the present invention.

DETAILED DESCRIPTION

In view of the wide variety of embodiments to which the principles ofthe present invention can be applied, it should be understood that theillustrated embodiments are exemplary only, and should not be taken aslimiting the scope of the present invention.

FIGS. 1A–1C are block diagrams illustrating an integration of a GPSreceiver with a magnetic field sensing device (i.e. a magneto-resistivesensor). The device 100 of FIGS. 1A and 1B includes a first portion 102,including a magneto-resistive sensor and wiring, and a second portion104, including GPS receiver circuitry. In a preferred embodiment, thesecond portion 104 also includes signal conditioning circuitry andcircuitry for ESD (electro-static discharge) protection for themagneto-resistive sensor in the first portion 102. As discussed below,the second portion 104 is particularly amenable to standardsemiconductor fabrication techniques, such as those used for CMOS(complementary metal oxide semiconductor). The first and second portions102, 104 are included within a single chip, so that the device 100 is adiscrete, one-chip design.

Prior attempts to integrate a GPS receiver and electronic compassingusing a magneto-resistive sensor have typically involved at least twochips placed separately on a printed circuit board, which likely resultsin a larger-sized end-user device (e.g. cell phone, portable device,watch, etc.) and increased complexity. The one-chip design of device100, however, provides reduced sized and added functionality. Thissmaller size may be useful in such applications as cell phones, handheldGPS units, and watches, for example. Further, this integrated designallows a user to determine a compass heading both while stationary andwhile moving. GPS (and other satellite-based systems) require the GPSreceiver to be moving at an approximate velocity of at least 10 m.p.h.relative to the surface of the earth in order to allow the GPS receiverto determine a compass heading, based on past and present position.Thus, if used in a cell phone, for example, the one-chip design ofdevice 100 could allow a user to determine both position and headingwhile standing or walking. Other applications may include industrial orautomotive uses.

The first and second portions 102, 104 of the device 100 may bemanufactured using standard RF/microwave processes, such as CMOS,gallium-arsenide (GaAs), germanium, BiCMOS (bipolarCMOS), InP (indiumphosphide), SOI (silicon-on-insulator), and MOI(microwave-on-insulator). While a technology like GaAs may provideadvantages in operational speed, reduced power consumption might best berealized through the use of other techniques, such as those involvingSOI (Silicon on Insulator) or MOI (Microwave-On-Insulator), a variationof SOI. In a preferred embodiment, the first portion 102 is manufacturedusing standard lithography, metallization, and etch processes. Thesecond portion 104 is preferably manufactured using Honeywell's MOI-50.35 micron processing, or another RF/microwave method, such as GaAsprocessing.

Integrating the magnetic field sensing device with the GPS receiver in asingle chip design may be accomplished in at least two ways. FIGS. 1Aillustrates a first embodiment where a magneto-resistive sensor 102 isfabricated on a single die along with the GPS receiver 104 and possiblyother circuitry, such as signal conditioning and ESD protectioncircuitry, for example. In the embodiment illustrated in FIG. 1A, theGPS receiver 104 and other circuitry and the magneto-resistive sensor102 are located in discrete layers in a single die.

FIG. 1B illustrates a second way in which a magnetic field sensingdevice can be integrated with a GPS receiver. In FIG. 1B, amagneto-resistive sensor 102 is fabricated on a first die, while the GPSreceiver 104 and signal conditioning circuitry are fabricated on asecond die. The first die and the second die may then be placed in closeproximity to one another and packaged within a single integrated circuitchip 106. In all cases, it may be advantageous to include one or moreelectrical connections between the GPS receiver 104 and themagneto-resistive sensor 102 to provide feedback, for example.Alternatively, the GPS receiver 104 and magneto-resistive sensor 102 maysimply be located physically close to one another with no intentionalelectrical interaction.

Additionally, FIG. 1C. illustrates a second embodiment of a single dieintegration wherein a magneto-resistive sensor 102 and a GPS receiver104 and other circuitry are contained in a single die. However, in theembodiment illustrated in FIG. 1C, wiring 108 and the magneto-resistivesensor 102 are contained in separate portions of the second portion ofthe die.

Some GPS receiver circuitry and signal conditioning circuitry maygenerate electromagnetic fields significant enough to influence theoperation of the magnetic field sensing device. As a result, thesensitive parts of the first portion 102 of the integrated device 100may need to be physically separated from parts of the second portion 104in order to provide optimal magnetic field sensing device operation. Theamount of separation may be determined using theoretical or empiricalmeans, for example.

As an alternative to introducing physical separation between potentiallyinterfering parts of the integrated device 100, a shielding layer may beprovided. FIGS. 2A–2C illustrate three exemplary configurations for sucha shield. The device 200 of FIG. 2A is a single die integration of amagnetic field sensing device 202 and a GPS receiver 204 with ashielding layer 206 located substantially between the two. The shieldinglayer 206 may extend over some of or over the entire interface betweenthe first and second portions 202, 204, depending on the characteristicsof the electromagnetic fields and the location of sensitive components.

FIG. 2B illustrates a single die integrated magnetic field sensingdevice 202 and GPS receiver 204 with a shielding layer 208 locatedwithin the second portion 204. Shielding layer 208 is a localized shieldwhich might be beneficial where the majority of the magnetic fieldeffects originate from a relatively small part of the second portion204. The shield 208 may also be advantageous in designs havingelectrical connections between the first and second portions 202, 204.However, shielding layer 208 could be made less localized wherenecessary to properly shield sensitive components.

FIG. 2C illustrates a multiple die, integrated magnetic field sensingdevice 202 and GPS receiver 204 with a shielding layer 210 locatedsubstantially between the magnetic field sensing device 202 and the GPSreceiver 204. The shielding layer 210 may extend over some of or overthe entire interface between the magnetic field sensing device 202 andthe GPS receiver 204, depending on the characteristics of theelectromagnetic fields and the location of sensitive components. Themagnetic field sensing device 202, the GPS receiver 204, and theshielding layer 210 are contained in a single-chip package 212. For allembodiments, use of a shielding layer will likely allow tighterintegration of the device 200 than use of physical separation ofphysical parts. While such a shielding layer may comprise metal or amagnetic material (e.g. NiFe film), other materials may also besuitable.

FIG. 3 illustrates an exemplary architecture of a device 300, in which aGPS receiver 302 may be implemented with a magnetic field sensing device304 on a single die. The GPS receiver circuitry (along with any signalconditioning circuitry and drivers for set and/or offset strapsassociated with the magnetic field sensing device portion) may befabricated largely within the GPS receiver underlayer 302, while amagneto-resistive sensor 304 may be fabricated above the planardielectric layer 306. Also shown in FIG. 3 are contacts 308 forconnecting the GPS receiver underlayer 302 with the magneto-resistivesensor 304. Additionally, NiFe permalloy structures 310 which are partof the magneto-resistive sensor 304 are shown.

In a preferred embodiment, the GPS receiver underlayer 302 may befabricated first. A substantially planar dielectric layer 306 (i.e.contact glass) is then deposited on the GPS receiver underlayer 302, ontop of which the magneto-resistive sensor 304 is then fabricated. TheGPS receiver underlayer 302 is fabricated first because its fabricationprocesses usually require the highest temperatures. Additionally, thefunction of the planar dielectric layer 306 is to provide asubstantially planar surface on which the magneto-resistive sensor canbe fabricated, as well as to electrically isolate the GPS receiverunderlayer 302 from the magneto-resistive sensor 304.

FIG. 4 illustrates a detailed view of an exemplary architecture of adevice 400, in which a GPS receiver may be implemented with a magneticfield sensing device on a single die. The GPS receiver circuitry (alongwith any signal conditioning circuitry and drivers for set and/or offsetstraps associated with the magnetic field sensing device portion) may befabricated largely within the CMOS/Bipolar underlayers 402, while amagneto-resistive sensor may be fabricated in layers 404–408, above theplanar dielectric layer 410. Also shown in FIG. 4 are various contactsV1–V3 and metallizations M1–M3, NiFe permalloy structures, a 1^(st)dielectric layer 408, a second dielectric layer 406, and a passivationlayer 404. In one embodiment, layers 404–408 are formed using standardlithography, metallization, and etch processes, while layers 410 and 402are formed using Honeywell's MOI-5 0.35 micron processing, or anotherRF/microwave method, such as GaAs processing. Other components of themagneto-resistive sensor (such as set, reset, and offset straps; signalconditioning circuitry, and ESD protection circuitry) may be included invarious locations in the layers 408–410 and 402, and are not fullyillustrated in FIG. 4.

For further information on magneto-resistive sensor designs, referencemay be made to the following patents and/or patent applications, all ofwhich are incorporated by reference herein:

-   -   U.S. Pat. No. 6,529,114, Bohlinger et al., “Magnetic Field        Sensing Device”    -   U.S. Pat. No. 6,232,776, Pant et al., “Magnetic Field Sensor for        Isotropically Sensing an Incident Magnetic Field in a Sensor        Plane”    -   U.S. Pat. No. 5,952,825, Wan, “Magnetic Field Sensing Device        Having Integral Coils for Producing Magnetic Fields”    -   U.S. Pat. No. 5,820,924, Witcraft et al., “Method of Fabricating        a Magnetoresistive Sensor”    -   U.S. Pat. No. 5,247,278, Pant et al., “Magnetic Field Sensing        Device”    -   U.S. patent application Ser. No. 09/947,733, Witcraft et al.,        “Method and System for Improving the Efficiency of the Set and        Offset Straps on a Magnetic Sensor”    -   U.S. patent application Ser. No. 10/002,454, Wan et al.,        “360-Degree Rotary Position Sensor”

In addition, U.S. Pat. No. 5,521,501, to Dettmann et al., titled“Magnetic Field Sensor Constructed From a Remagnetization Line and OneMagnetoresistive Resistor or a Plurality of Magnetoresistive Resistors”is also incorporated herein by reference, and may provide additionaldetails on constructing a magneto-resistive sensor.

FIG. 5 illustrates a plan view of one embodiment of a device 500 inwhich a GPS receiver is integrated with a magnetic field sensing deviceon a single die. The structures visible in FIG. 5 are attributablelargely to a magneto-resistive sensor (and other circuitry, such asset/offset drivers or magnetic sensor signal conditioning circuitryformed in the underlayers of the device 500). Exemplary parts of thedevice 500 include a magneto-resistive bridge 502, set/reset straps 504,offset straps 506, set/reset circuitry 508, 510, laser trim sites 512(for matching impedance of the legs of the magneto-resistive bridge502), ESD protection diode 514, operational amplifiers 516, contacts518, test sites 520, and GPS receiver components 522. Reference may bemade to the patents and patent applications incorporated above forfurther information.

FIG. 6 is a simplified block diagram of a GPS receiver 600. The GPSreceiver 600 receives signals 602 from at least three different GPSsatellites received by an antenna on the device. The received signals602 are then usually filtered by a passive bandpass prefilter 604 toreduce out-of-band RF interference and preamplified 604. Next, the RFsignals are typically downconverted to an intermediate frequency (IF)606, and converted from analog to digital 606. These signals are thensent to the digital signal processor (DSP) 608. From the DSP 608 thesignal undergoes navigation processing 610, which yields position,velocity, and time information 612. Because conventional processes areused, the particular GPS circuitry is not disclosed herein, as it isflexible. Thus, conventional GPS receiver designs implementable inCMOS/GaAs/BiCMOS, for example, can be utilized in accordance with thepresently disclosed embodiments.

FIG. 7 illustrates one application 700 for the integrated GPS receiverand magnetic field sensing device set forth herein. A user 702 is shownwith a cell phone 704 having a single-chip integrated GPS receiver andmagnetic field sensing device. The user 702 is able to obtain locationand heading information by orienting the cell phone 704 in the directionthe user 702 is facing, for example. The magnetic field sensing deviceis able to determine direction while the GPS receiver is able todetermine the user's 702 location. The combination provides synergisticeffects, such as the ability to perform database lookups to combinedirections with yellow page information. For example, a user 702 couldobtain a phone number for a business or residence the user is facing bycausing the cell phone 704 to transmit location and heading informationto a network server, which could respond with the phone number.

FIG. 8 illustrates another application 800 for the integrated GPSreceiver and magnetic field sensing device set forth herein. A user 802is show with a video camera 804 having a single-chip integrated GPSreceiver and magnetic field sensing device. The user 802 is able toobtain location and heading information by orienting the video camera804 in the direction the user is facing. The magnetic field sensingdevice is able to tell the user 802 what direction he is facing, whilethe GPS receiver is able to determine the user's 802 location. Thecombination provides synergistic effects, such as the ability to recordlocation and heading information which correlates to the footage beingrecorded by the user 802. This could allow the user 802 to lateridentify buildings or other landmarks that were recorded, as well asallow the user 802 to later find the same area where particular footagewas recorded. Of course, many other uses are possible as well. Becauseonly one chip is needed, rather than two or more, the overall size ofthe user's 802 device (e.g. digital camera, cell phone, portable device,watch, etc.) may be kept small.

Table 1, below, shows a simplified exemplary process for integrating aGPS receiver with a magnetic field sensing device. It is believed thatsuch a process is unique because, in the past, semiconductor foundrieshave gone to great lengths to prevent contamination of their processeswith materials typically used in manufacturing magnetic sensors. Inaddition, companies in the magnetic industries (e.g. disk drive headmanufacturers, etc.) have been separate from electronics companies, andtheir specialized manufacturing techniques have been kept largelyseparate from one another.

TABLE 1 Sample Manufacturing Process CMOS, Bipolar, GaAs, BiCMOS, InP,SOI, MOI underlayers (end front-end processing; begin back-endprocessing) Deposit contact glass (if any), reflow Form magnetic fieldsensing device layer Inspection and evaluation

In a preferred embodiment, the semiconductor device processing (i.e.CMOS, Bipolar, GaAs, etc.) is done at the front end, while the metalinterconnect and the magnetic field sensing device are done at the backend. Table 1 is intended to be generally applicable to any magneticfield sensing device manufacturing process, and thus does not includedetail on how to obtain particular architectures. Additional cleaningand other steps should be implemented as appropriate.

An exemplary embodiment of the present invention has been describedabove. Those skilled in the art will understand, however, that changesand modifications may be made to this embodiment without departing fromthe true scope and spirit of the present invention, which is defined bythe claims.

1. A single package sensor device comprising: GPS receiver circuitry;and at least one magnetic field sensing device adjacent to the GPSreceiver circuitry; wherein the GPS receiver circuitry and the at leastone magnetic field sensing device are collected within a singlesemiconductor chip package.
 2. The sensor device of claim 1 wherein theat least one magnetic field sensing device comprises a sensor selectedfrom one of the group consisting of a compassing sensor, an anisotropicmagneto-resistive (AMR) sensor, a giant magneto-resistive (GMR) sensor,a colossal magneto-resistive (CMR) sensor, a hall effect sensor, afluxgate sensor, and a coil sensor.
 3. The sensor device of claim 1wherein a dielectric layer is disposed between the GPS receivercircuitry and the at least one magnetic field sensing device.
 4. Thesensor device of claim 3 further comprising at least one connectionpathway in the dielectric layer for connecting the GPS receivercircuitry with the at least one magnetic field sensing device.
 5. Thesensor device of claim 4 further comprising conducting portions disposedin the at least one connection pathway.
 6. The sensor device of claim 3wherein the dielectric layer comprises contact glass.
 7. The sensordevice of claim 6 wherein the contact glass comprises a materialselected from one of the group consisting of silicon-nitride (Si3N4),borophosphosilicate glass (BPSG), silicon-oxide (SiO2), and any otheretchable contact glass that can be reflowed into a substantially planarsurface.
 8. The sensor device of claim 1 wherein there is at least oneconnection pathway for connecting the GPS receiver circuitry with the atleast one magnetic field sensing device.
 9. The sensor device of claim 8further comprising conducting portions disposed in the at least oneconnection pathway.
 10. The sensor device of claim 1 wherein the atleast one magnetic field sensing device includes at least one of a setstrap, a reset strap, and an offset strap.
 11. The sensor device ofclaim 10 wherein the GPS receiver circuitry includes driver circuitryfor any of the included set, reset, and offset straps.
 12. The sensordevice of claim 1, wherein the GPS receiver circuitry is formed from anyof complementary-metal-oxide-semiconductor (CMOS), gallium-arsenide(GaAs), germanium, bipolarCMOS (BiCMOS), indium phosphide (InP),silicon-on-insulator (SOI), and microwave-on-insulator (MOI)technologies.
 13. The sensor device of claim 1 wherein the GPS receivercircuitry is formed using MOI-5 0.35 micron technology.
 14. The sensordevice of claim 13 wherein the at least one magnetic field sensingdevice is formed using standard fabricating processes for formingmagneto-resistive sensors.
 15. The sensor device of claim 1 wherein atleast one shield is disposed between the GPS receiver circuitry and theat least one magnetic field sensing device.
 16. The sensor device ofclaim 15 wherein the at least one shield comprises a material selectedfrom the group consisting of metal, magnetic material, and otherisolating material.
 17. The sensor device of claim 15, wherein the atleast one shield prevents the GPS receiver circuitry from undesirablyaffecting the operation of the at least one magnetic field sensingdevice.
 18. The sensor device of claim 15, wherein the at least oneshield prevents the at least one magnetic field sensing device fromundesirably affecting the operation of the GPS receiver circuitry. 19.The sensor device of claim 1 wherein the at least one magnetic fieldsensing device is used for electronic compassing.
 20. The sensor deviceof claim 1 wherein the GPS receiver circuitry and the at least onemagnetic field sensing device are formed in at least two separate die,all die being contained in a single-chip package.
 21. The sensor deviceof claim 20 wherein the at least two separate die are electricallyconnected.
 22. The sensor device of claim 20 wherein the at least twoseparate die have no intentional electrical interaction.
 23. The sensordevice of claim 20 wherein the at least one magnetic field sensingdevice includes at least one of a set strap, a reset strap, and anoffset strap.
 24. The sensor device of claim 23 wherein the GPS receivercircuitry includes driver circuitry for any of the included set, reset,and offset straps.
 25. The sensor device of claim 20, wherein the GPSreceiver circuitry is formed from any ofcomplementary-metal-oxide-semiconductor (CMOS), gallium-arsenide (GaAs),germanium, bipolarCMOS (BiCMOS), indium phosphide (InP),silicon-on-insulator (SOI), and microwave-on-insulator (MOI)technologies.
 26. The sensor device of claim 20 wherein the GPS receivercircuitry is formed using MOI-5 0.35 micron technology.
 27. The sensordevice of claim 26 wherein the at least one magnetic field sensingdevice is formed using standard fabricating processes for formingmagneto-resistive sensors.
 28. The sensor device of claim 20 wherein atleast one shield is disposed between the GPS receiver circuitry and theat least one magnetic field sensing device.
 29. The sensor device ofclaim 28 wherein the at least one shield comprises a material selectedfrom the group consisting of metal, magnetic material, and otherisolating material.
 30. The sensor device of claim 29, wherein the atleast one shield prevents the GPS receiver circuitry from undesirablyaffecting the operation of the at least one magnetic field sensingdevice.
 31. The sensor device of claim 29, wherein the at least oneshield prevents the at least one magnetic field sensing device fromundesirably affecting the operation of the GPS receiver circuitry. 32.The sensor device of claim 20 wherein the at least one magnetic fieldsensing device is used for electronic compassing.